If you have been following any of the other battery threads, its well established that these cars suck down battery pretty fast when they sit, and don't adequately charge on short drives. Unfortunately the OP doesn't have a the ability to use a batter tender where they park.
Not sure if it's a parasitic drain, or just the fact that there are tons of electronics on these cars, or poor batteries from Ford.
I think also that once a battery is discharged once they really do suffer from then on. Letting them go flat and then using a booster to start them will not be a solution as the battery will be destroyed. It takes a LONG drive to recover from a cold start, I did a 5 hour drive in the summer (my car is a daily) and only right near the end did the voltage drop to around 13 volts indicating the battery was 'fully' charged (we know they only charge to 80%)
Not sure where you missed this but there are plenty of threads on here and other Ford forums / Forscan forums where it states the BMS restricts charge to 80% SOC to preserve battery life. In some cars you can change this using Forscan.Where on earth did you hear they only charge to 80%?That is 100% false. And 13v doesn't mean it's fully charged.
That is not true. A simple volt meter test proves this. There has been no such statements regarding the S650.Not sure where you missed this but there are plenty of threads on here and other Ford forums / Forscan forums where it states the BMS restricts charge to 80% SOC to preserve battery life. In some cars you can change this using Forscan.
That is 100% true
The running voltage of the vehicle is determined by the charging system (not the battery) and with modern alternators this will vary depending on battery SOC and other factors. It can be very complex but basically it will charge at a higher rate (around 14.5v) when needed but drop to around 13v when SOC is at or around 80%.
(9) Alternator Overcharging on a 2018 GT Premium | Page 2 | 2015+ S550 Mustang Forum (GT, EcoBoost, GT350, GT500, Bullitt, Mach 1) - Mustang6G.com
Question about changing battery charge rate in FORScan | F150gen14 -- 2021+ Ford F-150, Tremor, Raptor Forum (14th Gen) | News, Owners, Community, Discussions
Ford F150 Powerboost Owners 21+ | For those of you that have used Forscan to adjust the target battery charge level, what has been your experience with this mod compared to the factory... | Facebook
What is not true? What simple test with a voltmeter?
Do you not know how to test a battery? If you need me to explain what a voltage test is, then you shouldn't be arguing.What is not true? What simple test with a voltmeter?
ALL Ford cars and trucks use a BMS system in this way with a target SOC of 80% as a default
Check out the BCM settings here for the 2024 Mustang:
(28) 2024 Mustang FORScan List / Database / Spreadsheet (by Livinitup) | Mustang7G - 2024+ S650 Mustang Forum (Dark Horse, GT, EcoBoost, GT500, GT350, Mach 1)
726-080-02
Ehh?
Does the bms do the remote features disabled at 75% ?Ehh?
The engine is running in everything I have mentioned above, nothing to do with testing a battery with the engine off. I am well aware how to check a battery SOC on a non-running car.
Not sure why you are finding this so difficult to understand?
ALL Ford cars have a BMS that determines the charging of the 12v battery when the engine is running. It changes the output of the alternator (or DC-DC converter in EV's) between around 14.5v and 13v depending on the SOC of the 12v battery which has a target of 80% SOC as per the post above to prolong battery life and reduce the risk of overcharging. It will go a little above 80% at times but will also maintain that buffer to avoid reaching 100%.
The comment about my own car and monitoring the voltage on a long journey confirms this.
I'm not making this up you know - all the evidence is there as I have posted and it isn't just Ford that use this system. Why would people be changing the target SOC setting in their Mustangs and other cars if it wasn't there?
There is simply nothing to argue about
